-LRB- CNN -RRB- The widow of the man whose life was portrayed in the acclaimed film `` American Sniper '' has penned a heartfelt letter to him on their 13th anniversary .

Taya Kyle posted her letter March 16 on the Chris Kyle Facebook page , where she proclaimed , `` I miss you and I love you . I feel you in my heart and soul so strongly . I am more blessed to have been your wife than anything else in my life . ''

`` Today , I have a choice . I can bury myself under the covers and acknowledge the pain of missing you and mourn the future anniversaries without you , '' she wrote . `` Or , I can celebrate never having a day without you in my heart because you loved me enough to leave me a lifetime of memories and beauty . ''

Kyle , a Navy SEAL , has been credited as the most successful sniper in United States military history . Bradley Cooper was nominated for an Academy Award for his portrayal of Kyle in this winter 's film `` American Sniper , '' which was based on Kyle 's bestselling autobiography .

The film , directed by Clint Eastwood , has become the highest-grossing war movie ever .

Why ` American Sniper ' is a smash hit

Kyle and his friend Chad Littlefield were shot and killed at a gun range in 2013 by Eddie Ray Routh . A Texas jury found Routh guilty of capital murder in February , and he was sentenced to life in prison without the possibility of parole .

Jury finds Eddie Ray Routh guilty in ` American Sniper ' case

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Taya Kyle posted the letter on their 13th wedding anniversary

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`` American Sniper '' is the highest-grossing war movie

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A man was found guilty in Kyle 's death in February